As the summer heats up, itís taking a toll in your yard
Want to know where the summer is heating up? Take a stroll and look at yards and trees. There, along the edges of lawn and leaf, you can find some of the hottest spots in town.
High heat takes its toll on many plants, and after our cool, moist
start to the season trees with lush canopies are now in water stress. In spring the abundance of water in our soils resulted in dense canopies and vigorous growth. But now that the ground has dried and temperatures soar, the soil doesnít have as much moisture for trees to pull for all of their leaves.
To deal with this, trees are thinning canopies by dropping extra leaves they canít support under hot dry conditions. This is normal and particularly common in ash and cottonwood. Like most slimming regimens this doesnít harm the tree, it simply helps it live within its means.
Cooking on the Patio
Even tough plants can curl up from broiling temperatures if they are planted by southwest facing walls and patios. These areas form pockets of reflected heat that increase the need for plants to cool themselves. They accomplish this by evapotranspiration: pulling water up through the plant to evaporate from leaves. If your plant is not mulched the ground dries quickly, so put down a layer 4 inches thick to protect roots.
Blooming Brown Spots
One of the most obvious areas suffering from heat is the lawn. Brown spots are blooming everywhere, and sprinkler sections at local hardware stores are sizzling with action.
Most brown areas are due to poor watering of the lawn. To check the coverage of water on your lawn, take a long, slender screwdriver and, beginning in the green areas and walking toward the brown, push the screwdriver into the soil at random intervals. If the blade slides easily into the ground in the green grass, but comes to a screeching halt in the brown areas, there is much less moisture in those spots and the irrigation must be adjusted.
Donít forget to adjust the run times on automatic sprinkler systems to deliver more water to lawns, flowers, vegetables and trees. Our weather patterns have dried out, leaving much of the moisture necessary for plants up to humans to deliver. Perennials and annuals that have put on good growth since spring need to have water increased to accommodate their larger size. Trees planted years ago with drip irrigation should have the lines and emitters checked to make certain they are delivering enough water for older trees.
Most herbaceous plants will look droopy in mid afternoon Ė much like gardeners do Ė but those with enough water will spring back once evening arrives. Plants that donít rebound in the evening should be given a drink, and if this doesnít help, check their stems for signs of disease.
Check your lawn before increasing water to it by walking across it the afternoon before watering is scheduled. If the footprints stay visible 30 minutes or longer after walking on it, the grass is drying out a little too much in between watering.
Get Professional Help
With any change in irrigation, be alert to signs of trouble. Lawns donít need water every day, and if you are running your sprinklers that often you may need professional help. The Colorado Association of Lawn Care Professionals (lawncarecolorado.org) and the International Society for Arboriculture, Rocky Mountain Chapter (isarmc.org/) have listings for businesses in your area to help correct problems.
Carol OíMeara is with the Colorado State University Extension office at the Boulder County Fairgrounds in Longmont. Contact her by calling 303-678-6238 or e-mailing firstname.lastname@example.org .co.us. Colorado State University Extension, together with Boulder County Parks and Open Space, provides unbiased, research-based information, about consumer and family issues, horticulture, natural resources, agriculture and 4-H youth development. For more information, contact the Extension at the Boulder County Fairgrounds, 9595 Nelson Road, Box B, Longmont, 303-678-6238, or visit www.coopext.colostate.edu/boulder.